@ddljohn-- I think that sexually stimulating medications are safe as long as they are used under the supervision of a doctor and according to directions. Of course, all medications can have side effects, even natural herbs have side effects. I think that some of the negative feedback about these medications come from people who don't use them properly and who take higher than recommended doses.
If these medications really had such severe side effects, I'm sure that the FDA would do something about it. So we can use them, but we should use them wisely. And those who are taking medications for chronic health conditions should check with their doctor to make sure that the drugs will not interact negatively with one another.